Substation Transformers
Electrical Apparatus
Primary or Secondary Unit
210-15
GENERAL
Cooper Power Systems Primary or
Secondary Unit Substation
Transformers are designed to meet
exact customer specifications.
Flexibility in design, combined with
the highest quality manufacturing
processes and equipment, enable
Cooper Power Systems to provide a
product optimized to the customer’s
requirements. All units meet applicable ANSI, NEMA, IEEE Standards
and NEC® and CEA specifications.
Unit substation transformers are
available with enclosed sidewallmounted bushings for connections to
primary and/or secondary switchgear.
Substation transformers are made with
a wide range of core steels and winding conductors to meet total owning
cost or material requirements. Flexible
core and tank construction enables
your dimensional requirements to be
met.
Cooper Power Systems transformers
are available with standard electrical
grade mineral insulating oil or other
dielectric coolants manufactured by
Cooper Power Systems.
Unit substation transformers intended
for indoor use are filled with R-Temp®
fluid, a less-flammable, high molecular
weight hydrocarbon with a flawless
fire safety record. Electrical codes
recognize the advantages of using
R-Temp fluid both indoors and outdoors for fire sensitive applications.
R-Temp fluid-filled units meet OSHA
and Section 450-23,1996 NEC
requirements. Transformers intended
for outdoor applications may be filled
with R-Temp fluid or normally formulated hydro-refined mineral oil.
March 1998 • Supersedes 11/94
Printed in U.S.A.
Figure 1.
Secondary unit substation transformer equipped with transition flange and full
length cabinet.
1
Primary or Secondary Unit
RAPID PRESSURE
RISE RELAY
Monitors rapid rise of
internal pressure.
PRESSURE/VACUUM
GAUGE
Available with
bleeder valve.
TANK LIFTING LUGS
Lift hooks welded to the
tank at each corner for
lifting.
LIQUID
TEMPERATURE GAUGE
For easy monitoring of oil
temperature. Available
with multiple alarm
contacts.
FILLING/FILTER
PRESS
CONNECTION
One-inch
upper filling
and filter press
connection.
FLANGE
Allows connection
to high-voltage
gear.
FULL
LENGTH
CABINET
DE-ENERGIZED
TAP CHANGER
Tap changer is
externally operable.
LIQUID LEVEL
GAUGE
Monitors oil level.
Available with
alarm contacts.
NAMEPLATE
Laser-scribed
anodized
aluminum.
COOLING
RADIATORS
Detachable, bolt-on
radiators with valves
are available.
BASE
Suitable for skidding,
rolling and jacking.
GROUND PADS
Non-corrosive, stainless
steel ground pads on
the front and rear.
CONTROL BOX
Weather-resistant, dust-proof,
NEMA-rated control box for
controls and alarm contacts.
DRAIN/FILTERING VALVE
The combination drain and
filtering valve contains a
fluid sampling device.
Figure 2.
Secondary unit substation transformer with standard features and optional accessories.
2
PRESSURE RELIEF DEVICE
Activated by excessive tank
pressure.
210-15
STANDARD FEATURES
OPTIONAL ACCESSORIES
PROTECTION OPTIONS
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
■
De-energized tap changer,
externally operable
Extra-heavy, welded-in-place
lifting lugs and jack pads
Sidewall mounted high-voltage
porcelain bushings
Sidewall mounted low-voltage
molded epoxy bushings with NEMA
six-hole spades
Tank bases designed to allow
skidding or rolling in any direction
One-inch upper filling plug with
filter press connection
One-inch combination drain/filtering
valve with sampling device
Available in ANSI #61 Light Gray or
ANSI #70 Sky Gray
Tank interior is painted light gray,
improving visibility for field inspection and servicing
Pressure test connection
Dial-type thermometer
Dial-type liquid level gauge
Pressure vacuum gauge
Stainless steel grounding pads
Laser-scribed anodized aluminum
nameplate
Cooling radiators are welded
directly to the tank
Standard grade mineral insulating
oil (for outdoor applications)
Pressure relief device
■
■
■
■
■
■
■
■
■
■
Primary and secondary termination
enclosure options
■ Throat
■ Flange
■ Top- or bottom-entry air terminal
chamber
■ Top- or bottom-entry full length
cabinet
Pressure vacuum bleeder valve
Cover mounted pressure relief
device (for oil-cooled units; standard
with R-Temp units)
Detachable, bolt-on radiators with
valves
Monitoring devices
■ Dial-type thermometer with
alarm contacts (standard with
FA Fan Package)
■ Liquid level gauge with alarm
contacts
■ Pressure/vacuum gauge with
alarm contacts
■ Cover mounted pressure relief
device with alarm contacts
■ Rapid pressure rise relay
■ Optional seal-in panel
Winding temperature indicator with
alarm contacts
R-Temp less-flammable fluid and
other environmentally desirable
fluid options
Primary air disconnect switch
Forced air fan control package
■ Package includes fans, NEMA
3R control box, fan controls,
dial-type thermometer with
alarm contacts.
Nitrogen blanket with purge valves
(3 psi)
Control box
■
Surge arresters
■ Distribution, intermediate, or
station class
Kyle® Vacuum Fault Interrupter
(VFI)
3
Primary or Secondary Unit
ELECTRICAL DATA
TABLE 4
Three-phase, Dual Temperature kVA Ratings
TABLE 1
Three-phase, Single Temperature kVA
Ratings
Three-phase kVA
Self-cooled and forced-air cooled with dual rated 55/65° C temperature rise
55° C Rise
65° C Rise
55° C Rise
65° C Rise
OA
0A
OA/FA
OA/FA
500
560
575
644
750
840
862
965
1000
1120
1150
1288
1500
1680
1725
1932
2000
2240
2300
2576
+12%
2500
2800
3125
3500
3750
4200
4687
5250
5000
5600
6750
7000
7500
8400
9375
10500
10000
11200
12500
14000
Three-phase kVA
Self-cooled and forced-air cooled
with 65° C temperature rise
65° C Rise
65° C Rise
OA
OA/FA
500
575
750
862
1000
+15%
1150
1500
1725
2000
2300






2500
3750
5000
7500
10000
+25%



3125
 4687
 6250
9375
 12500
TABLE 5
Insulation Test Levels
kV Class
TABLE 2
Percent Impedance Voltage1
kV BIL
Class
45-150
200
250
1
2
3
1.2
2.5
5.0
8.7
15.0
25.0 (Grd Y Only)
25.0
34.5 (Grd Y Only)
34.5
46.0
Low Voltage
< 2400 V
≥ 2400 V
2
3
5.75
6.50
7.25
7.00
7.75
7.50
The standard tolerance is ± 7.5%.
Option for 6.75% is available.
Option for 5.50% is available.
Induced Test
180 or 400 Hz-7200 Cycle
TWICE
RATED
VOLTAGE
kV BIL
Distribution
Power
30
45
60
75
95
125
150
125
150
200
45
60
75
95
110
150
150
150
200
250
Applied Test
60 Hz (kV)
10
15
19
26
34
40
50
50
70
95
TABLE 6
Temperature Rise Ratings 0 - 3300 feet (0-1000 meters)
TABLE 3
Audible Sound Levels
4






Self-cooled,
Two Winding
kVA Rating
NEMA Average
dB, OA
dB, FA
500
501-700
701-1000
1001-1500
1501-2000
2001-2500
2501-3000
3001-4000
4001-5000
5001-6000
6001-7500
7501-10000
56
57
58
60
61
62
63
64
65
66
67
68
67
67
67
67
67
67
67
67
67
68
70
71
Unit Rating
Ambient Temperature Max.
Ambient Temperature 24 Hour Av.
Temperature Rise Winding1
Temperature Rise Hotspot
1
Standard
Optional
65° C
40° C
30° C
65° C
80° C
55/65° C
40° C
30° C
55° C
65° C
Average Rise by resistance. Refer to NEMA Standards TRI; ANSI Standard C57.12.00.
Note: Derate kVA by 0.4% for each 100 M (330 ft.) that the altitude is above 1000 M (3300 ft.).
210-15
TABLE 7
Oil Filled – Aluminum Windings 55/65°C Rise1
Base Dimensions
(in.)
C
kVA
500
750
1000
1500
2000
2500
>2500
X3
X2
H3
D
Drawing Dimensions
(in.)
H2
X1
X0
H1
1
TOP VIEW
8"
Width
51
56
58
54
57
68
Depth
A
B
C
D
35
69
50
40
59
36
69
55
36
56
36
69
57
42
62
36
78
53
54
75
38
78
56
55
109
40
78
67
50
99
* Consult Factory Representative
Weights, gallons of fluid and dimensions are for reference only, and not for construction. Please contact
Cooper Power Systems for exact dimensions.
TABLE 8
R-Temp® Filled – Aluminum Windings 55/65°C Rise1
Base Dimensions
(in.)
Drawing Dimensions
(in.)
kVA
500
750
1000
1500
2000
2500
>2500
A
55"
55"
B
1
ELEVATION
Figure 3.
High-voltage left (Segment 2) shown.
High-voltage right (segment 4) also
available.
Width
51
56
58
56
60
68
Depth
A
B
C
D
35
69
50
40
59
36
69
55
42
62
36
69
57
42
84
36
78
55
62
83
40
78
59
56
111
40
78
67
58
115
* Consult Factory Representative
TABLE 9
Oil Filled – Copper Windings 55/65°C Rise1
Base Dimensions
(in.)
500
750
1000
1500
2000
2500
>2500
3
4
1
ANSI segment
designation
Approx.
Total
Gallons Weight (Ibs.)
Of Fluid (With Fluid)
325
6,300
355
7,600
375
8,400
425
10,800
530
13,500
620
16,300
Weights, gallons of fluid and dimensions are for reference only, and not for construction. Please contact
Cooper Power Systems for exact dimensions.
Drawing Dimensions
(in.)
kVA
2
Approx.
Total
Gallons Weight (Ibs.)
Of Fluid (With Fluid)
335
6,300
355
7,300
370
8,200
400
9,800
455
12,000
595
14,680
1
Width
51
55
59
51
59
59
Depth
A
B
C
D
34
69
50
39
59
38
69
54
39
60
38
69
58
45
66
40
78
50
56
78
38
78
58
57
113
38
78
58
57
113
* Consult Factory Representative
Approx.
Total
Gallons Weight (Ibs.)
Of Fluid (With Fluid)
320
5,500
375
7,500
390
8,750
435
11,000
475
13,250
500
14,500
Weights, gallons of fluid and dimensions are for reference only, and not for construction. Please contact
Cooper Power Systems for exact dimensions.
TABLE 10
R-Temp® Filled – Copper Windings 55/65°C Rise1
Base Dimensions
(in.)
Drawing Dimensions
(in.)
kVA
500
750
1000
1500
2000
2500
>2500
1
Width
47
55
55
59
59
63
Depth
A
B
C
D
34
69
46
39
59
34
69
54
39
59
35
69
54
40
78
36
78
58
51
102
36
84
58
59
118
38
84
62
60
120
* Consult Factory Representative
Gallons
Of Fluid
310
350
350
450
510
550
Approx.
Total
Weight (Ibs.)
(With Fluid)
5,250
6,750
8,000
11,500
13,500
15,500
Weights, gallons of fluid and dimensions are for reference only, and not for construction. Please contact
Cooper Power Systems for exact dimensions.
5
Primary or Secondary Unit
38"
34"
38"
34"
10.5"
9"
8"
BUSHINGS
CL
18"
2" (TYP.)
2" (Typ.)
15"
20"
8"
BUSHINGS
CL
10.5"
9"
42"
4"
Ø 0.50"
12 HOLES
9"
9"
9"
40"
10.5"
44"
9"
10.5"
Figure 4.
Throat.
4"
9"
Ø 0.50"
16 HOLES
9"
9"
9"
36"
Figure 7.
Flange.
38.3"
10"
BUSHING
CL
38.3"
34"
24"
24"
34"
FRONT VIEW
(with Lift-Off Front Panel)
18"
BUSHING
CL
10"
22"
FRONT VIEW
(with Lift-Off Front Panel)
18"
Figure 5.
Air terminal chamber-bottom entry.
22"
Figure 8.
Air terminal chamber-top entry.
38.3"
38.3"
10"
BUSHING
CL
24 "
BUSHING
CL
55"
55"
18"
FRONT VIEW
(with Lift-Off Front Panel)
22"
Figure 6.
Full length cabinet-bottom entry.
18"
22"
Figure 9.
Full length cabinet-top entry.
6
FRONT VIEW
(with Lift-Off Front Panel)
210-15
CONSTRUCTION
Core
Transformer tanks are pressure-tested
to withstand 7 psig without permanent
distortion and 15 psig without rupture.
The three-legged, step-lap mitered
core construction is manufactured
using a high-quality cutting machine.
For maximum efficiency, cores are
precisely stacked, virtually eliminating
gaps in the corner joints.
Five-legged wound core or shell-type
triplex designs are used for wye-wye
connected transformers, and other
special transformer designs.
Cores are manufactured with precision cut, burr-free, grain-oriented silicon steel. Many grades of core steel
are available for optimizing core loss
efficiency.
Tank Finish
Coils
Substation transformers feature a
rectangular coil configuration with
wire-wound, high-voltage primaries
and sheet-wound secondaries. The
design minimizes axial stress developed by short circuits and provides
for magnetic balancing of tap
connections.
Coils are wound using the highest
quality winding machines providing
exacting tension control and conductor placement for superior short-circuit
strength and maximum efficiency.
Extra mechanical strength is provided
by diamond pattern, epoxy coated
paper insulation, used throughout the
coil, with additional epoxy at heavy
stress points. The diamond pattern
distribution of the epoxy and carefully
arranged ducts, provide a network of
passages through which cooling fluid
can freely circulate.
Coil assemblies are heat-cured under
calculated hydraulic pressure to
ensure performance against short-circuit forces.
Core and Coil Assemblies
Substation transformer core and coil
assemblies are braced with heavy
heavy steel end plates to prevent the
rectangular coil from distorting under
fault conditions. Plates are clamped in
place using presses, and welded or
bolted to form a solid core and coil
assembly.
Tanks
Transformer tanks are designed for
high strength, and ease of handling,
installation, and maintenance. Tanks
are welded using precision-cut, hotrolled, pickled and oiled steel. They
are sealed to protect the insulating
fluid and other internal components.
An advanced multi-stage finishing
process exceeds ANSI C57.12.28
standards. The eight-state pretreatment
process assures coating adhesion
and retards corrosion. It converts tank
surfaces to a nonmetallic, water
insoluble iron phosphate coating.
The three-step, epoxy primer (E-coat)
provides a barrier against moisture, salt
and corrosives. The electrostaticallyapplied, oven-cured polyester power
coat (P-coat) enhances resistance to
abrasion and impact. A urethane final
coat seals and adds ultraviolet
protection.
Vacuum Processing
Transformers are dried and filled with
filtered insulating fluid under vacuum,
while secondary windings are energized. Coils are heated to drive out
moisture, ensuring maximum penetration of fluid into the coil insulation
system. Special attention to moisture
removal is the major reason for
Cooper’s track record of superior
reliability and service life.
Cooling System
Oil-Air (OA) cooling is provided with
transformers rated 500 kVA. A choice
of OA-FFA (Future Forced Air) or
OA-FA (Forced Air) cooling is provided
with units rated 750 kVA and above.
Insulating Fluid
Cooper Power Systems transformers
are available with standard electrical
grade mineral insulating oil or other
dielectric coolants manufactured by
Cooper Power Systems. The highly
refined oil is tested and degassed to
assure a chemically inert product with
minimal acid ions. Special additives
minimize oxygen absorption and
inhibit oxidation. To ensure high
dielectric strength, the oil is retested
for dryness and dielectric strength,
refiltered, heated, dried, and stored
under vacuum before being added to
the completed transformer. R-Temp
fluid, manufactured by Cooper Power
Systems under strict quality control for
optimum transformer cooling characteristics, provides higher dielectric
strength than mineral oil. The special
formulation is less flammable as
defined by the National Electric Safety
Code, as well as non-toxic and
biodegradable. Envirotemp® FR3 fluid,
the fluid used in Envirotran® transformers is a fire resistant, natural
ester-based fluid. Envirotemp FR3 fluid
offers the advantage of a seed oil-based
dielectric coolant with food grade
additives, in addition to increased fire
safety when compared to mineral oil.
R-Temp and Envirotemp FR3 fluid
can be used in a substation transformer next to buildings or inside
buildings with suitable containment
provisions.
SUBSTATION VFI
TRANSFORMER
The VFI transformer combines a conventional Cooper Power Systems distribution transformer with the proven
Kyle Vacuum Fault Interrupter (VFI).
This combination provides both voltage transformation and transformer
overcurrent protection in one space
saving, money saving package.
The substation VFI transformer with
transformer protection protects the
transformer and provides proper coordination with upstream protective
devices. When a transformer fault or
overload condition occurs, the VFI
breaker trips and isolates the transformer.
The three-phase VFI breaker has
independent single-phase initiation,
but is three-phase mechanically
gang-tripped. A trip signal on any
phase will open all three phases. This
feature eliminates single-phasing of
three-phase loads. It also enables the
VFI breaker to be used as a threephase loadbreak switch. Because the
VFI breaker is resettable, restoring
three-phase service is faster and
easier.
R-TRAN™ FM APPROVED
TRANSFORMER
Cooper Power Systems’ R-Tran
Transformer is FM Approved for
indoor locations. Factory Mutual
Research Corporation’s approval of
the R-Tran transformer line makes it
easy to comply and verify compliance
with the 1996 National Electrical
Code (NEC®) section 450-23, LessFlammable Liquid-Filled Transformer
Requirements for both indoor and
outdoor locations.
7
Primary or Secondary Unit
FM Approved R-Tran transformers
offer the user the benefit of a transformer that can be easily specified to
comply with NEC, and makes FM
Safety Data Sheet compliance simpler, while also providing maximum
safety and flexibility for both indoor
and outdoor installations. Because
the “FM Approved” logo is readily visible on the transformer and its nameplate, NEC compliance is now easily
verifiable by the inspector.
Substation R-Tran FM Approved
transformers from Cooper Power
Systems are manufactured under
strict compliance with FMRC
Standard 3990, and are filled with FM
Approved R-Temp fire-resistant
dielectric coolant.
Primary Air Disconnect
Switch
■
■
■
■
■
Provides economical, visible disconnect primary loadbreak switching.
Fully coordinated and packaged
with the transformer by Cooper
Power Systems.
Meets IEEE/ANSI C37.20.3, NEMA
SG-5 and related standards.
Standard features
■ Switch
■ Three-pole, two-position,
gang-operated air interrupter;
unfused
■ Standard ratings:
■ 600 A continuous and
loadbreak; 40 kA fault
close and momentary
■ 5 kV (60 kV BIL) or 15 kV
(95 kV BIL)
■ Enclosure
■ Standardized modular selfsupporting, bolted design
■ Mechanical safety interlock
prevents access when switch
is closed or closing of switch
when door is open.
Optional Features
■ 1200 A continuous and load
break current rating; 61 kA fault
close and momentary. Requires
1200 A copper bus option.
■ Key interlocks (single cylinder)
for interlocking primary switch
with secondary main circuit
protective device.
■ Auxiliary switch for remote
indication of primary switch
position
■ Where high interrupting ratings
and short-circuit protection are
desired: current-limiting nonexpulsion power fuses
■ Where lower interrupting
ratings are adequate:
■ Non-disconnect power fuses
■ Disconnect power fuses
© 1998 Cooper Power Systems, Inc.
R-Temp® Envirotemp®, Envirotran® and Kyle® are registered trademarks of
Cooper Industries, Inc.
R-Tran™ is a trademark of Cooper Industries, Inc.
National Electric Code® and NEC® are registered trademarks of the National
Fire Protection Association.
UL® is a registered trademark of Underwriter’s Laboratories, Inc.
8
QUALITY CONTROL
■
■
All transformers are subjected to
Routine and Design Performance
Tests per the requirements of ANSI
C57.12.00
Each transformer must pass the
following tests:
■ Resistance measurements of all
windings at the rated voltage
connection of each unit, and at
the tap extremes.
■ Ratio tests at the rated voltage
connection and at all tap
connections.
■ Polarity and phase-relation tests
at the rated voltage connections.
■ No load losses at rated voltage
on the rated voltage connection.
■ Exciting current at rated voltage
on the rated voltage connection.
■ Impedance and load loss at
rated current on the rated
voltage connection of each unit.
■ Temperature rise tests
■ Performed in accordance with
ANSI Standards.
■ Performed on one unit of a
given rating when test records
on an essentially duplicate
unit are not available.
■ Applied potential test
■ Induced potential test
■ Routine impulse test
P.O. Box 1640
Waukesha, WI 53187
www.cooperpower.com
MI
Printed on Recycled Paper
3/98